1. Field of the Invention
The present invention generally relates to an optical reading apparatus having an optical scanner for scanning information on objects, and more particularly to a bar code scanner that collectively reads bar codes existing in a scanning field of a laser beam by scanning a laser beam in a plurality of directions.
2. Description of the Related Art
There are roughly two types of bar code scanners. One is a bar code scanner that reads bar code symbol by bringing its reading part in contact with a bar code label or bringing the reading part very close to the bar code label. For example, a CCD touch scanner and pen scanner, etc., that are frequently used in small-sized retail stores belong to this type.
On the other hand, the fixed laser scanner and hand laser scanner can read bar code labels in a scanning field having a predetermined spatial spread by scanning a laser beam in various directions.
The CCD touch scanner and pen scanner described above have limits to the positional relationship between the reading part thereof and a bar code label of an object to be read. Therefore, only a single bar code can be read by one reading operation.
On the other hand, although a fixed laser scanner and a hand-held laser scanner have, respectively, predetermined reading depths, only a single bar code can be read by a single scanning operation in prior arts.
The reason resides in that a strict limitation is implied in terms of the time required for a reading process in major uses of this type of bar code scanner. Fixed laser scanners are mainly installed in a cash register in large-scaled retail stores. In such a use, a bar code symbol must be read at the instant when the bar code label crosses the reading field of a bar code scanner as the operator moves an article across it.
FIG. 19 shows a configurational example of a prior art fixed laser scanner. Also, FIG. 20 is a view explaining a reading action made by a prior art fixed laser scanner.
A laser beam is scanned in various directions by an optical system 401. When a bar code label is scanned by the laser beam, light diffused by the bar code label is incident into a photo acceptance unit 403, and is converted to electric signals corresponding to the intensity thereof, where the electric signals are inputted to a signal processing part 404. As shown in FIG. 20(a), the signal processing part 404 removes noise by binarizing the inputted electric signals in compliance with a predetermined slicing level. Also, a demodulating part 405 shown in FIG. 19 analyzes the pulse width and pulse interval of binarized signals obtained by the signal processing part 404, and generates reading data corresponding to the bar code symbol recorded in the bar code label described above on the basis of the results of analysis. Then, the demodulating part 405 outputs the reading data to the host computer 407 via an interface part 406.
In order to read bar code symbols at a high efficiency by effectively utilizing the binarized signals obtained in a limited time, the demodulating part 405 employs a block data composite process and a label stitching method, etc.
The block data composite process is a technique for generating binarized signals corresponding to the entire bar code symbol by combining, as shown in FIG. 20(b), binarized signals obtained by scanning a range including half a block from a guard bar to a center bar and binarized signals obtained by scanning a range including the other half of the block from the center bar to the other guard bar.
Also, the label stitching method is a technique for generating binarized signals corresponding to the entire bar code symbol by detecting the respective binarized signals obtained in further detailed ranges, and the overlapped portion of these binarized signals and by combining these.
By employing these techniques, then, regardless of the alignment of articles when an operator moves the articles in the reading field of a bar code scanner, the bar code symbol can be read at high accuracy on the basis of the binarized signals obtained in a short period of time during which the articles cross the reading field of the bar code scanner.
The above-described block data composite process and label stitching method are based on the assumption that, in any case thereof, binarized signals inputted within the time corresponding to one reading operation is generated by diffusely reflected light from a single bar code label.
In uses in which these techniques are requisite and indispensable, this is the basis that the number of bar codes read by one reading operation by a fixed laser scanner is limited to a single bar code symbol.
However, recently, laser scanners are being developed and downsized to hand-held laser scanners. In line therewith, there is a possibility that the above-described hand-held laser scanners can be utilized in uses where a touch scanner and a pen scanner have conventionally been used.
It is therefore an object of the invention to provide an optical reading apparatus capable of collectively reading a plurality of optically readable codes resting in a field scanned by a laser beam.
It is a further object of the invention to greatly reduce the work load applied to an operator of an optical reading apparatus represented by a scanning apparatus, by collectively reading a plurality of different bar code labels indicating various symbols resting in a limited field on, for example, a checkout counter.
The above-described objects are achieved by a first scanning apparatus comprising: a discriminating part that discriminates and extracts a set of consecutive data which meet predetermined conditions among candidates obtained by a signal converting part; a choosing part for choosing a set of consecutive data different from each other from a group of the sets of consecutive data; and an outputting part for outputting reading result in response to the input of chosen set of consecutive data.
The first scanning apparatus like this is capable of extracting a set of consecutive data that consecutively expresses all modules constituting bar code symbols, by inputting candidates obtained by converting electric signals, which are obtained by a photoelectric converting part, into the discriminating part by a signal converting part.
Only sets of consecutive data that are different from each other are chosen from a group of the sets of extracted consecutive data by the choosing part, and the sets of consecutive data overlapped due to the same bar code symbols having been scanned two or more times are excluded, wherein by outputting the remaining sets of consecutive data via an outputting part, the plurality of bar code labels described above can be collectively read, and the reading result corresponding thereto can be outputted.
Also, the above-described objects can be achieved by a first optical reading apparatus that is provided with: a scanning part that generates a scanning laser beam capable of scanning optically readable symbols by scanning a laser beam; a transducer that receives light reflected from the symbol and generates electric signals corresponding to the amount of the received light; a demodulating part that demodulates the electric signals outputted from the transducer and reproduces data recorded as the symbol; a discriminating part for extracting sets of data that are different from each other among the data demodulated by the demodulating part; a numeric inputting part that receives numeric data; and a comparing part for comparing the numeric data inputted from the numeric inputting part with the number of sets of data extracted by the discriminating part.
The first optical reading apparatus as described above is capable of collectively reading these symbols according to the electric signals obtained when scanning a plurality of symbols by a scanning laser beam.
By an optical reading apparatus as such, which can discriminate demodulated data that are different from each other among the demodulated data obtained when a scanning laser beam has scanned a plurality of optically readable symbols, it is possible to read these symbols at one time.
In addition, the above-described objects are achieved by a scanning apparatus provided with: a data inputting part that inputs data regarding the bar code labels which are objects to be read; and an editing part that edits the reading result according to of the data and the sets of consecutive data chosen by the choosing part.
Such a scanning apparatus is capable of obtaining a reading result consisting of bar code symbols corresponding to all the bar code labels which are the objects to be read, by the editing part duplicating the bar code symbols, and editing the reading result corresponding to an adequate set of consecutive data according to the data received by the data inputting part.
That is, since it is possible to securely generate the reading result corresponding to all the bar code labels of the object to be read, by editing the reading result according to the chosen sets of consecutive data and information upon receiving input of the information intuitively grasped by an operator, it is possible to further reduce the work load of the operator.
Further, the above-described objects are achieved by a scanning apparatus provided with an outputting part comprising: a reporting part for reporting a reading result on the reading result generated by the editing part; and a transmission controlling part that transmits the reading result in response to input of an instruction of approving the reading result.
Since such a scanning apparatus presents the result of having collectively read a plurality of bar code labels to an operator and can transmit the reading result to the host computer upon the approval of the reading result, it is possible to prevent erroneous reading result from being transmitted.
Also, the above-described objects are achieved by a scanning apparatus provided with: a total number inputting part that inputs the total number of bar code labels which are objects to be read; a judging part that judges, according to the total number of bar code labels and the number of the chosen sets of consecutive data, whether or not the reading operation is completed; and an output controlling part that instructs to the choosing part that the chosen sets of consecutive data are transferred to the outputting part, in response to the result of judgement.
Since such a scanning apparatus can receive by the total number inputting part the input of the total number of objects to be read, which is intuitively grasped by an operator, it is possible to collectively read a plurality of bar code labels automatically without any excess or shortage, according to the total number of objects to be read, by automatically judging the completion of a reading operation in cases where the objects to be read differ from each other.
Also, the above-described objects are achieved by a scanning apparatus having the total number inputting part combined by being provided with an operation mechanism for inputting data, and a first generating part that generates data indicating the number in response to an operation of the operation mechanism.
In such a scanning apparatus, the total number of bar code labels which are intuitively grasped by an operator is inputted by a simple operation and is provided for the completion judgement of the reading operation.
In addition, the above-described objects are achieved by a scanning apparatus having the total number inputting part combined by being provided with a detecting part for extracting a candidate corresponding to the bar code symbol indicating the number; and second generating part that generates data indicating the number according to the candidate. In such a scanning apparatus, an adequate number can be inputted by utilizing a function inherent to the scanning apparatus, whereby it becomes unnecessary to newly add additional hardware components to input the number.
The above-described objects are achieved by a scanning apparatus provided with: a total number inputting part that inputs the total number of bar code labels which are objects to be read; a judging part that judges whether or not a reading operation is completed on the basis of the total number of bar code labels and the number of the chosen sets of consecutive data; and a notifying part that notifies information to support the reading operation in response to the judgement result.
Such a scanning apparatus receives the input of the total number of objects to be read, which is intuitively grasped by an operator, automatically judges, based on the total number of the objects to be read, whether or not a reading operation is completed, and notifies the operator of information corresponding to the judgement result, and the scanner can thereby support the operator in charge of reading operations.
The above-described objects are achieved by a scanning apparatus provided with a notifying part having an indicating part that displays messages or the like in response to the judgement result. Since such a scanning apparatus can display messages or adequate images showing whether or not the reading operation is completed, it is possible to support the reading operation by more intuitively grasped information.
The above-described objects are achieved by a scanning apparatus provided with a notifying part having an audio outputting part that outputs sound responsive to the judgement result. According to such a scanning apparatus, since it is possible to output a confirmation sound showing that the reading operation has been successfully completed, and an alarm sound showing that the reading operation is continuing, it is possible to support a reading operation by information that can be more intuitively grasped.
The above-described objects are achieved by a scanning apparatus provided with a reporting part that reports the progress of a reading operation of bar code labels.
In such a scanning apparatus, since information regarding these sets of consecutive data is prepared by the reporting part according to the sets of consecutive data chosen by the choosing part and is provided to an operator, it is possible to facilitate the grasping of an operator of the progress status of the reading operation.
The above-described objects are achieved by a scanning apparatus provided with: a modal inputting part that inputs a modal instruction; a verifying part that verifies correctness of the sets of consecutive data chosen by the choosing part; and a transfer controlling part that controls a transfer action from the choosing part to the outputting part in response to the verification result.
In such scanning apparatus, it is possible to verify the correctness of a set of consecutive data that are repeatedly extracted by the discriminating part by mutually comparing the sets of consecutive data when a specified reading mode is inputted by the modal inputting art, based on the fact that in the case a plurality of bar code labels having the same bar code symbols are object to be read, the same sets of consecutive data repeatedly extracted by the discriminating part. And, the transfer controlling part can control whether or not these sets of consecutive data are transferred to the outputting part.
The above-described objects are achieved by a scanning apparatus provided with a modal inputting part that inputs a modal instruction, and an outputting part combined by being provided with an output controlling part that instructs output of the reading result responsive to a predetermined operation and an sending part that outputs the reading result corresponding to the sets of consecutive data chosen by the choosing part whenever an instruction is inputted from the output controlling part. Such a scanning apparatus can repeatedly output the reading result corresponding to the chosen sets of consecutive data by the number of times by which instructions are inputted by the output controlling part when a specified mode is inputted by the modal inputting part.
The above-described objects are achieved by an optical reading apparatus provided with a discriminating part having a selecting part that selects sets of data expressing optically readable symbols from the top to the end thereof without any interruption. Such an optical reading apparatus ensures the correctness of the sets of data extracted by the discriminating part.
In addition, the above-described objects are achieved by an optical reading apparatus equipped with an indicating part that indicates sets of data extracted by the discriminating part. Such an optical reading apparatus provides an operator with information regarding the progress status of reading operations and can support the reading operations.